The use of robotics is well established as a manufacturing expedient, particularly in applications where human handling is inefficient and/or undesirable. One such circumstance is in the semiconductor arts, in which robotics are used to handle wafers during various process steps. Such process steps may include, by way of example, chemical mechanical planarization (CMP), etching, deposition, passivation, and various other processes in which a sealed and/or “clean” environment must be maintained, such as to limit the likelihood of contamination and to ensure that various specific processing conditions are met.
Current practice in the semiconductor arts to robotically handle these wafers often includes the use of an end effector operably attached to the robotics, such as in order to load semiconductor wafers from a loading stack into the various processing ports that may correspond to the aforementioned exemplary process steps. The robotics are employed to deploy the end effector to retrieve the wafer from a particular port or stack, such as before and/or after processing in an associated process chamber. The wafer may thus be shuttled by the robotics connectively associated with the end effector to subsequent ports for additional processing. When the wafer processing stages are complete, the robotics may then return the processed semiconductor wafer to a loading port, and may, again using the end effector, then retrieve the next wafer for processing by the system. It is typical that a stack of several semiconductor wafers is processed in this manner using the end effector during each process run.
Typical end effectors hold the wafer on its bottom side, such as using backside suction provided by, for example, vacuum draw eyelets on the end effector. The application of other mechanical forces directly to the wafer is atypical, in part because the application of mechanical forces is generally understood to have a high likelihood of damaging or contaminating the wafer.
Accordingly, there is a need for an end effector that may readily handle and transfer very thin semiconductor wafers, preferably of multiple wafer sizes and for multiple process steps, without damaging or contaminating such wafers.